An independent review of the country’s biggest beef recall says consumers may have been exposed to contaminated beef from an Albertameat packer on two other occasions in the months leading up to last fall’s food safety crisis.

Industry guidelines call for plants to hold and test all product when the level of positive results for E. coli 0157: H7 exceed five per cent.

But the investigation report released today found XL Foods Inc. took no apparent action when results spiked to near or above 10 per cent last summer during two days of production that have been linked to 18 illnesses in Canada and were the reason that hundreds of products were ultimately pulled from store shelves across the continent.

And the three-member review team also learned that in December 2011 company officials had shipped trim destined for use in ground beef despite the fact that over 40 per cent of the samples tested positive for a potentially fatal bacteria.

On another occasion, the level of positive tests exceeded 12 per cent in March 2012, but the Brooks facility company didn’t act to isolate other batches of beef that may have also been tainted.

A Canada Food Inspection Agency employee, left, looks on as beef from the XL Foods cattle processing plant is dumped at a landfill site near Brooks, Alta., Monday, Oct. 22, 2012.

“This is indicative of long-standing problems at XL Foods,” the report said.

“For its part, CFIA was clearly not monitoring the company’s food safety enhancement program and identifying deficiencies as carefully as they should have been.”

Officials with Nilsson Bros. Inc, the plant’s operators at the time, were not immediately available for comment.

The Canadian Food Inspection Agency said it has tightened rules on how meat packers respond to “high event periods” and will spend nearly $16 million over the next three years to establish inspection verification teams that will be a “second set of eyes” watching front line staff at food establishments.